In the approximately 45 years since the development of the first crude computer, our society has seen a virtual explosion of information storage as well as information processing machines. With the advent of the personal computer, this information explosion has permeated virtually every facet of our daily lives. In the business community, personal computers are used to store and process a large amount of material which was previously maintained in paper files. Similarly, many homes now include a personal computer for the storage of personal data as well as the processing of other types of information.
During the infancy of the computer industry, when only very large companies or the government were able to afford to purchase and maintain relatively large mainframe computers provided with bulky storage media, security for access to this storage media was generally maintained by limiting access to the area in which the computer was stored as well as access to the computer itself. Typically, an authorized user was issued either a computer password or security card allowing access to the computer and any files included in the storage media utilized with the company. In other words, the person attempting to gain access to the computer must possess the knowledge and/or the tools of the authorized user. However, used in the context of today's smaller personal computers and the utilization of relatively small, portable storage media, this type of security program has proven to be inadequate. For example, if the password or security card would be stolen from the authorized personnel, computer access to an authorized person would be granted. Additionally, since the storage media is relatively small in size and, due to the need for allowing access to the material provided on this storage media to various authorized personnel remote from one another, it is important that a system be developed in which the storage media can be sent to various locations without the security of the material on the media being compromised.
In this context, several methods have been developed for protecting access to software programs stored on storage media such as read-only-memory (ROM). Examples of these devices are discussed in U.S. Pat. Nos. 4,757,468 issued to Domenik et al and 4,740,890 issued to William. Both of these patents describe apparatuses for protecting software programs which will be distributed on a magnetic disk or similar storage media. Verification routines provided directly on the storage media are utilized to protect access to the entire program. However, no device has been developed in which storage media itself is utilized to protect non-program information, such as textual material, data, graphs, or other digitally stored material. Furthermore, since various personnel may be granted access to only selective material which would be on the storage disk, the scenarios described with respect to the Domenik et al and William patents would not be applicable to an instance in which various personnel would be granted access to only a limited portion of the material provided on the storage media. This is important since only a single master print of any entire file may be manufactured and distributed to various personnel with limited access of material granted to each of the personnel. If limiting access was not possible, various storage devices and quite possibly many more storage devices, must be manufactured and given to each of the personnel, based upon the section of the material to which each individual has been granted access.
Similarly, no device was discovered in which the storage media, provided with software program information thereon, is used to allow access to only a portion of the program information, or one or more programs from a plurality of programs.